| /* |
| * Copyright (c) 2013, 2018, Red Hat, Inc. All rights reserved. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #ifndef SHARE_VM_GC_SHENANDOAH_SHENANDOAHSCHEDULERTHREAD_HPP |
| #define SHARE_VM_GC_SHENANDOAH_SHENANDOAHSCHEDULERTHREAD_HPP |
| |
| #include "gc/shared/gcCause.hpp" |
| #include "gc/shared/concurrentGCThread.hpp" |
| #include "gc/shenandoah/shenandoahHeap.hpp" |
| #include "gc/shenandoah/shenandoahPadding.hpp" |
| #include "gc/shenandoah/shenandoahSharedVariables.hpp" |
| #include "runtime/task.hpp" |
| #include "utilities/ostream.hpp" |
| |
| // Periodic task is useful for doing asynchronous things that do not require (heap) locks, |
| // or synchronization with other parts of collector. These could run even when ShenandoahConcurrentThread |
| // is busy driving the GC cycle. |
| class ShenandoahPeriodicTask : public PeriodicTask { |
| private: |
| ShenandoahControlThread* _thread; |
| public: |
| ShenandoahPeriodicTask(ShenandoahControlThread* thread) : |
| PeriodicTask(100), _thread(thread) {} |
| virtual void task(); |
| }; |
| |
| // Periodic task to notify blocked paced waiters. |
| class ShenandoahPeriodicPacerNotify : public PeriodicTask { |
| public: |
| ShenandoahPeriodicPacerNotify() : PeriodicTask(PeriodicTask::min_interval) {} |
| virtual void task(); |
| }; |
| |
| class ShenandoahControlThread: public ConcurrentGCThread { |
| friend class VMStructs; |
| |
| private: |
| typedef enum { |
| none, |
| concurrent_normal, |
| stw_degenerated, |
| stw_full |
| } GCMode; |
| |
| // While we could have a single lock for these, it may risk unblocking |
| // GC waiters when alloc failure GC cycle finishes. We want instead |
| // to make complete explicit cycle for for demanding customers. |
| Monitor _alloc_failure_waiters_lock; |
| Monitor _gc_waiters_lock; |
| ShenandoahPeriodicTask _periodic_task; |
| ShenandoahPeriodicPacerNotify _periodic_pacer_notify_task; |
| |
| public: |
| void run_service(); |
| void stop_service(); |
| |
| private: |
| ShenandoahSharedFlag _gc_requested; |
| ShenandoahSharedFlag _alloc_failure_gc; |
| ShenandoahSharedFlag _graceful_shutdown; |
| ShenandoahSharedFlag _heap_changed; |
| ShenandoahSharedFlag _do_counters_update; |
| ShenandoahSharedFlag _force_counters_update; |
| GCCause::Cause _requested_gc_cause; |
| ShenandoahHeap::ShenandoahDegenPoint _degen_point; |
| |
| shenandoah_padding(0); |
| volatile size_t _allocs_seen; |
| shenandoah_padding(1); |
| volatile size_t _gc_id; |
| shenandoah_padding(2); |
| |
| bool check_cancellation_or_degen(ShenandoahHeap::ShenandoahDegenPoint point); |
| void service_concurrent_normal_cycle(GCCause::Cause cause); |
| void service_stw_full_cycle(GCCause::Cause cause); |
| void service_stw_degenerated_cycle(GCCause::Cause cause, ShenandoahHeap::ShenandoahDegenPoint point); |
| void service_uncommit(double shrink_before, size_t shrink_until); |
| |
| bool try_set_alloc_failure_gc(); |
| void notify_alloc_failure_waiters(); |
| bool is_alloc_failure_gc(); |
| |
| void reset_gc_id(); |
| void update_gc_id(); |
| size_t get_gc_id(); |
| |
| void notify_gc_waiters(); |
| |
| // Handle GC request. |
| // Blocks until GC is over. |
| void handle_requested_gc(GCCause::Cause cause); |
| |
| bool is_explicit_gc(GCCause::Cause cause) const; |
| |
| bool check_soft_max_changed() const; |
| |
| public: |
| // Constructor |
| ShenandoahControlThread(); |
| ~ShenandoahControlThread(); |
| |
| // Handle allocation failure from normal allocation. |
| // Blocks until memory is available. |
| void handle_alloc_failure(ShenandoahAllocRequest& req); |
| |
| // Handle allocation failure from evacuation path. |
| // Optionally blocks while collector is handling the failure. |
| void handle_alloc_failure_evac(size_t words); |
| |
| void request_gc(GCCause::Cause cause); |
| |
| void handle_counters_update(); |
| void handle_force_counters_update(); |
| void set_forced_counters_update(bool value); |
| |
| void notify_heap_changed(); |
| |
| void pacing_notify_alloc(size_t words); |
| |
| void start(); |
| void prepare_for_graceful_shutdown(); |
| bool in_graceful_shutdown(); |
| |
| char* name() const { return (char*)"ShenandoahControlThread";} |
| |
| // Printing |
| void print_on(outputStream* st) const; |
| void print() const; |
| }; |
| |
| #endif // SHARE_VM_GC_SHENANDOAH_SHENANDOAHSCHEDULERTHREAD_HPP |